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Funding: This research was funded by four naval organizations: the US Navy Living Marine Resources program (LMR), the Netherlands Ministry of Defence, the UK Ministry of Defense (Dstl) and the French Ministry of Defense (DGA-TN). Controlled exposure experiments (CEEs) have demonstrated that naval pulsed active sonar (PAS) can induce costly behavioral responses in cetaceans similar to antipredator responses. New generation continuous active sonars (CAS) emit lower amplitude levels but more continuous signals. We conducted CEEs with PAS, CAS and no-sonar control on free-ranging sperm whales in Norway. Two panels blind to experimental conditions concurrently inspected acoustic-and-movement-tag data and visual observations of tagged whales and used an established severity scale (0–9) to assign scores to putative responses. Only half of the exposures elicited a response, indicating overall low responsiveness in sperm whales. Responding whales (10 of 12) showed more, and more severe responses to sonar compared to no-sonar. Moreover, the probability of response increased when whales were previously exposed to presence of predatory and/or competing killer or long-finned pilot whales. Various behavioral change types occurred over a broad range of severities (1–6) during CAS and PAS. When combining all behavioral types, the proportion of responses to CAS was significantly higher than no-sonar but not different from PAS. Responses potentially impacting vital rates i.e., with severity ≥4, were initiated at received cumulative sound exposure levels (dB re 1 μPa2 s) of 137–177 during CAS and 143–181 during PAS. Publisher PDF

Funding: This research has been part of the 3S (Sea mammals, Sonar, Safety) project funded by the US Office of Naval Research, the Royal Norwegian Navy, the Norwegian Ministry of Defence, the Defence Research and Development Department of the Netherlands Ministry of Defence, and the French Ministry of Defence (DGA). Eavesdropping, the detection of communication signals by unintended receivers, can be beneficial in predator-prey interactions, competition, and cooperation. The cosmopolitan killer whale Orcinus orca has diverged into several ecotypes which exhibit specialised diets and different vocal behaviours. These ecotypes have diverse ecological relationships with other marine mammal species, and sound could be a reliable sensory modality for eavesdroppers to discriminate between ecotypes and thereby respond adaptively. Here, we tested whether humpback whales Megaptera novaeangliae in the Northeast Atlantic responded differently to playback of the sounds of 2 killer whale ecotypes, Northeast Atlantic herring-feeding killer whales representing food competitors and Northeast Pacific mammal-eating killer whales simulating potential predators. We used animal-borne tags and surface visual observations to monitor the behaviour of humpback whales throughout the playback experiments. Humpback whales clearly approached the source of herring-feeding killer whale sounds (5 of 6 cases), suggesting a ‘dinner-bell’ attraction effect. Responses to mammal-eating killer whale sounds varied with the context of presentation: playback elicited strong avoidance responses by humpback whales in offshore waters during summer (7 of 8 cases), whereas the whales either approached (2 of 4 cases) or avoided (2 of 4 cases) the sound source in inshore waters during winter. These results indicate that humpback whales may be able to functionally discriminate between the sounds of different killer whale ecotypes. Acoustic discrimination of heterospecific sounds may be widespread among marine mammals, suggesting that marine mammals could rely on eavesdropping as a primary source of information to make decisions during heterospecific encounters. Publisher PDF

This paper focuses on the sound reduction of light earth at the wall scale. It aims at gaining knowledge and providing informations to professional building workers to help them in the acoustic optimization of biobased walls. Experimentations have been performed in controlled conditions using the intensimetry method, on 22 different samples to investigate thickness effect, wood frame effect, coating effect together with different light earth implementations (shuttering, spraying). These data were then confronted to two modelling approaches, the mass law estimate and a Transfer Matrix Method computation. It is shown that light earth performance can be satisfactorily predicted, whatever the wall configuration using the Transfer Matrix Method computation with isotropic elastic and porous layers . The study brings finally a good understanding of the physical phenomena occurring in biobased concretes, depending on the presence of coatings. For light earth, it also appears that mass law yields to a good approximation of the single-number rating for some configurations including at least one coating.

The experimental characterization of most of the hygrothermal properties of bio-based porous materials, which are characteristic for their double-scale porosity, requires for the samples to stabilize their liquid water content. Furthermore, such measurements often take several weeks to several months. In contrast, acoustical measurements can be realized very quickly by using simple and relatively inexpensive test benches such as Kundt's tube. In this article, we investigate the existence of relationships between the hygrothermal and acoustical parameters of the porous media (porosity, resistivity, tortuosity, etc.), in order to provide ways to by-pass hygrothermal measurements by performing an indirect characterization of the material properties using acoustical measurements. Two expressions have been found to properly estimate the thermal conductivity and the water vapor permeability of the studied hemp and sunflower pith composites from acoustical measurements. However, further tests will be needed in order to establish the limits of these estimations (for which materials and in which conditions are they applicable) and further research will be made to shed light on the cause of these relationships. These two properties are capital in the conception of new eco-responsible building materials since a low thermal conductivity helps to improve energy efficiency, and the water vapor permeability plays a major role on thermal inertia, moisture regulation and on comfort inside the building. With further research, these results are expected to accelerate the development of sustainable construction materials and to better consider the complex hygrothermal behavior of such materials.

Modeling a wind turbine sound field involves taking into account the main aeroacoustic sources that are generally dominant for modern wind turbines, as well as environmental phenomena such as atmospheric conditions and ground properties that are variable in both time and space. A crucial step to obtain reliable predictions is to estimate the relative influence of environmental parameters on acoustic emission and propagation, in order to determine the parameters that induce the greatest variability on sound pressure level. Thus, this study proposes a Morris sensitivity analysis of a wind turbine noise emission model combined with a sound propagation model in downwind conditions. The emission model is based on Amiet's theory and propagation effects are modeled by the wide-angle parabolic equation. The whole simulation takes into account ground effects (absorption through acoustic impedance and scattering through surface roughness) and micrometeorological effects (mean refraction through the vertical gradient of effective sound speed). The final results show that the parameters involved in atmospheric refraction and in ground absorption have a significant influence on sound pressure level. On the other hand, in the context of this study the relative air humidity and the ground roughness parameters appear to be negligible on sound pressure level sensitivity.

Background: Hepatic injury secondary to congestive heart failure is well described, however, only limited data exist about the possible impact of acute cardiac dysfunction on the liver. We aimed to explore the possible cardio-hepatic interaction in patients with myocardial infarction. Material and methods: A single-center retrospective cohort study of 1339 ST elevation myocardial infarction (STEMI) patients who underwent primary coronary intervention between June 2012 to June 2019. Echocardiographic examinations were performed to assess left ventricular ejection fraction (LVEF) and central venous pressure (CVP). Patients were stratified into four groups by their LVEF and CVP levels: LVEF ≥ 45%, and CVP ≤ 10 mm/Hg (n = 853), LVEF < 45% with CVP ≤ 10 mm/Hg (n = 364), EF ≥ 45%, with CVP > 10 mm/Hg (n = 61), and LVEF < 45% with CVP > 10 mm/Hg (n = 61). Patients were evaluated for baseline and peak liver enzymes including alanine transaminase (AST), alanine aminotransferase (ALT), gamma glutamyl transferase (GGT), alkaline phosphatase (ALP), and bilirubin. Results: Greater severity of cardiac dysfunction was associated with worse elevation of liver enzymes. We found a graded increase in mean levels of maximal ALT, first and maximal ALP, and first and maximal GGT values. Using propensity score matching to estimate the impact of cardiac dysfunction on liver injury, we chose patients with the worst cardiac function parameters: (LVEF < 45% and CVP >10 mm/Hg; n = 61) and compared them to matched patients with better cardiac function (n = 45). We found a significantly higher level of maximal ALT, first and maximal ALP, and GGT values in the group with the worst cardiac function parameters (p < 0.05). Conclusions: Among patients with STEMI, the combination of decreased LVEF and venous congestion was associated with liver enzymes elevation suggesting a possible cardio-hepatic syndrome.

Research funding was provided by the US Office of Naval Research, the DGA/TN (France), the UK Natural Environmental Research Council, and the Ministries of Defence of Norway and The Netherlands. PLT acknowledges funding received from the MASTS pooling initiative (The Marine Alliance for Science and Technology for Scotland). MASTS is funded by the Scottish Funding Council (Grant reference HR09011) and contributing institutions. CC acknowledges statistical support provided by the Multi-study OCean acoustics Human effects Analysis (MOCHA) project funded by the United States Office of Naval Research (Grant N00014-12-1-0204). Killer whales (KW) may be predators or competitors of other cetaceans. Since their foraging behavior and acoustics differ among populations ('ecotypes'), we hypothesized that other cetaceans can eavesdrop on KW sounds and adjust their behavior according to the KW ecotype. We performed playback experiments on long-finned pilot whales (Globicephala melas) in Norway using familiar fish-eating KW sounds (fKW) simulating a sympatric population that might compete for foraging areas, unfamiliar mammal-eating KW sounds (mKW) simulating a potential predator threat, and two control sounds. We assessed behavioral responses using animal-borne multi-sensor tags and surface visual observations. Pilot whales barely changed behavior to a broadband noise (CTRL-), whereas they were attracted and exhibited spyhops to fKW, mKW, and to a repeated-tonal upsweep signal (CTRL+). Whales never stopped nor started feeding in response to fKW, whereas they reduced or stopped foraging to mKW and CTRL+. Moreover, pilot whales joined other subgroups in response to fKW and CTRL+, whereas they tightened individual spacing within group and reduced time at surface in response to mKW. Typical active intimidation behavior displayed to fKW might be an antipredator strategy to a known low-risk ecotype or alternatively a way of securing the habitat exploited by a heterospecific sympatric population. Cessation of feeding and more cohesive approach to mKW playbacks might reflect an antipredator behavior towards an unknown KW ecotype of potentially higher risk. We conclude that pilot whales are able to acoustically discriminate between familiar and unfamiliar KW ecotypes, enabling them to adjust their behavior according to the perceived disturbance type. Postprint

This paper describes the development and physical properties of a new, binderless, and light biobased particleboard, made of sunflower pith. It is first shown that such boards of densities ranging between 50 and 100 kg/m3 can be manufactured using combined action of heat and pressure. Then, acoustical and thermal performances of the particleboards are characterized. Acoustically, raw boards exhibit modest sound absorption, since constrictions between particles are too thin to enable the propagation. This observation is confirmed with the modeling of the material, and an optimization is performed with perforations, and endows the boards with really interesting absorption properties. Thermally, measurements demonstrate that these sunflower particleboards are very performing insulator, with conductivities ranging from 38 to 42 mW/m/K, and that this performance is not strongly affected by the acoustical optimization.

International audience; Over the last 20 years, a statistical acoustic model has been developed to predict the reverberant sound field in buildings. This model is based on the assumption that the propagation of the reverberant sound field follows a transport process and, as an approximation, a diffusion process that can be easily solved numerically. This model, initially designed and validated for rooms with purely diffuse reflections, is extended in the present study to mixed reflections, with a proportion of specular and diffuse reflections defined by a scattering coefficient. The proposed mathematical developments lead to an analytical expression of the diffusion constant that is a function of the scattering coefficient, but also on the absorption coefficient of the walls. The results obtained with this extended diffusion model are then compared with the classical diffusion model, as well as with a sound particles tracing approach considering mixed wall reflections. The comparison shows a good agreement for long rooms with uniform low absorption (α = 0.01) and uniform scattering. For a larger absorption (α = 0.1), the agreement is moderate, due to the fact that the proposed expression of the diffusion coefficient does not vary spatially. In addition, the proposed model is for now limited to uniform diffusion and should be extended in the future to more general cases.

Research funding was provided by the US Office of Naval Research and the Ministries of Defence of Norway, the Netherlands and France as well as the UK Natural Environmental Research Council. A key issue when investigating effects of anthropogenic noise on cetacean behavior is to identify the biological significance of the responses. Predator presence can be considered a natural high-level disturbance stimulus to which prey animals have evolved adaptive response strategies to reduce their risk of predation by altering behavior away from fitness-enhancing activities such as foraging. By contrasting the type and magnitude (duration, severity, consistency) of behavioral responses to anthropogenic noise and playback of killer whale (KW) sounds that simulated predator presence, this study aimed to provide a relative index of the disturbance level as an indication of the biological significance of responses to the anthropogenic stimulus. Using multi-sensor tags as well as visual observations of surface behavior of adult male sperm whales, we assessed a comprehensive range of behavioral metrics that could reduce individuals’ fitness if altered for a biologically relevant duration. Combining previously published results and new analyses, we showed that the responses to 1-2 kHz upsweep naval sonar and to KW playback were very similar, including horizontal avoidance, interruption of foraging or resting activities and an increase in social sound production. However, only KW playbacks elicited grouping behaviors, indicating that this social response component was specific to predator detection. Animals responded to a lesser extent to 6-7 kHz upsweep naval sonar, indicating weaker disturbance effects. Our study demonstrates the benefit of using anti-predator responses as a reference of disturbance when evaluating the relative impacts of anthropogenic stimuli, which can be of particular interest in studies of threatened species such as sperm whales. Publisher PDF

Publisher's version (útgefin grein), Impact assessments for sonar operations typically use received sound levels to predict behavioural disturbance in marine mammals. However, there are indications that cetaceans may learn to associate exposures from distant sound sources with lower perceived risk. To investigate the roles of source distance and received level in an area without frequent sonar activity, we conducted multi-scale controlled exposure experiments ( n = 3) with 12 northern bottlenose whales near Jan Mayen, Norway. Animals were tagged with high-resolution archival tags ( n = 1 per experiment) or medium-resolution satellite tags ( n = 9 in total) and subsequently exposed to sonar. We also deployed bottom-moored recorders to acoustically monitor for whales in the exposed area. Tagged whales initiated avoidance of the sound source over a wide range of distances (0.8-28 km), with responses characteristic of beaked whales. Both onset and intensity of response were better predicted by received sound pressure level (SPL) than by source distance. Avoidance threshold SPLs estimated for each whale ranged from 117-126 dB re 1 µPa, comparable to those of other tagged beaked whales. In this pristine underwater acoustic environment, we found no indication that the source distances tested in our experiments modulated the behavioural effects of sonar, as has been suggested for locations where whales are frequently exposed to sonar., The research described in this paper was supported by US Office of Naval Research (ONR grants N00014-15-1-2533 and N00014-16-1-3059), US Strategic Environmental Research and Development Program (SERDP award RC-2337), the French Ministry of Defence (DGA) and the Netherlands Ministry of Defence. P.L.T. acknowledges support from the MASTS pooling initiative (Marine Alliance for Science and Technology for Scotland; supported by the Scottish Funding Council, grant reference HR09011, and contributing institutions). The funding sources had no role in the planning, execution, analysis or writing of this study.

This experimental and modelling study provides a general overview of the acoustical performance of hemp-lime and hemp-clay for building thermal insulation at the material scale. It is based on statistically robust experimental results from more than 100 hemp-clay samples, together with the analysis of a large hemp-lime database. In hemp-clay mixes, our experimental results show the concentration of hemp in a mix has a first order effect on the acoustical performance, while binder fluidity and clay type have no effect. Another conclusion of this study is that hemp-clay and hemp-lime behave acoustically in a similar way. For both materials, experimental sound absorption and transmission curves can be modelled with a physical-based four-parameters approach. The close agreement between experimental measurements and modelling highlights the good level of understanding of the physical phenomena responsible for the acoustical behavior of hemp concrete. A classification is finally proposed in terms of density to be used as a general guideline to evaluate or optimize the acoustical performances of hemp-based concrete.

In the context of global amphibian decline, monitoring and restoration programmes are important. Acoustic monitoring is a possible approach for underwater vocalising species like the rapidly declining European common spadefoot toad (Pelobates fuscus). In this study, our aim was to design a dedicated software detector to be used in combination with programmable audio recorders to process the large amount of data generated by long‐term acoustic monitoring and to use it for investigating the seasonal and circadian patterns of P. fuscus vocal activity. The software detector targets advertisement calls of the species. Based on acoustic analysis of that call, we developed a detector that utilises both frequency and time features of the calls. Data collected during three breeding seasons in four known or potential P. fuscus breeding sites of north‐eastern France were used to build a ground truth in order to test the performance of the detector. Then, we used the detector for analysing four acoustic monitoring campaigns conducted in two different sites over two breeding seasons to gain insight into the seasonal and circadian patterns of vocal activity of this species. Evaluation of the P. fuscus call detector against a ground truth returned false‐positive rates below 1.5% and true‐positive rates ranging from 53% to 73%. These figures are compatible with long‐term monitoring of the presence of the species. Running the software detector on standard hardware, the computation time for post‐processing the 360 hr of a typical 3‐month monitoring campaign was less than 1 day. The seasonal pattern of P. fuscus underwater vocal activity is more complex than previously recognised. Over the whole ostensible 3‐month breeding season, the actual time window for vocalising and breeding can last from a few days up to several weeks and may be split into clearly distinct episodes. When vocalisations occurred at both night‐ and daytime, the circadian vocal activity of P. fuscus occasionally proceeded uninterrupted for 24 hr but usually a several hour lull occurred immediately prior to sunset. When vocalisations occurred at both night‐ and daytime, the vocal activity pattern followed a bimodal distribution with a nocturnal highest peak of activity and a second peak occurring in the morning. Our results demonstrate that it is feasible to monitor presence of P. fuscus in north‐eastern France using a dedicated software detector combined with programmable audio recorders. Based on the outcomes of the detector applied to long‐term audio data sets, we reveal temporal patterns of the vocal activity of the species and subsequently provide recommendations for attended and unattended acoustic monitoring. Locked until 16.4.2019 due to copyright restrictions. This is the peer reviewed version of the following article: [Automated acoustic monitoring of endangered common spadefoot toad populations reveals patterns of vocal activity], which has been published in final form at [https://onlinelibrary.wiley.com/doi/abs/10.1111/fwb.13111]. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.

This work was funded by NL Ministry of Defence, NOR Ministry of Defence, United States Office of Naval Research (N00014-08-1-0984, N00014-10-1-0355, and N00014-14-1-0390), and FR Ministry of Defence (DGA) (public market n°15860052). KA was supported by the Japan Society for the Promotion of Science Bilateral Open Partnership Joint Research Program. Air-breathing marine predators that target sub-surface prey have to balance the energetic benefit of foraging against the time, energetic and physiological costs of diving. Here we use on-animal data loggers to assess whether such trade-offs can be revealed by the breathing rates (BR) and timing of breaths in long-finned pilot whales (Globicephela melas). We used the period immediately following foraging dives in particular, for which respiratory behavior can be expected to be optimized for gas exchange. Breath times and fluke strokes were detected using onboard sensors (pressure, 3-axis acceleration) attached to animals using suction cups. The number and timing of breaths were quantified in non-linear mixed models that incorporated serial correlation and individual as a random effect. We found that pilot whales increased their BR in the 5-10min period prior to, and immediately following, dives that exceeded 31m depth. While pre-dive BRs did not vary with dive duration, the initial post-dive BR was linearly correlated with duration of >2 min dives, with BR then declining exponentially. Apparent net diving costs were 1.7 (SE 0.2) breaths per min of diving (post-dive number of breaths, above pre-dive breathing rate unrelated to dive recovery). Every fluke stroke was estimated to cost 0.086 breaths, which amounted to 80-90% average contribution of locomotion to the net diving costs. After accounting for fluke stroke rate, individuals in the small body size class took a greater number of breaths per diving minute. Individuals reduced their breathing rate (from the rate expected by diving behavior) by 13-16% during playbacks of killer whale sounds and their first exposure to 1-2kHz naval sonar, indicating similar responses to interspecific competitor/predator and anthropogenic sounds. Although we cannot rule out individuals increasing their per-breath O2 uptake to match metabolic demand, our results suggest that behavioral responses to experimental sound exposures were not associated with increased metabolic rates in a stress response, but metabolic rates instead appear to decrease. Our results support the hypothesis that maximal performance leads to predictable (optimized) breathing patterns, which combined with further physiological measurements could improve proxies of field metabolic rates and per-stroke energy costs from animal-borne behavior data. Publisher PDF

The authors would like to thank sponsors, NL Ministry of Defence, NOR Ministry of Defence, U.S. Office of Naval Research (N00014-08-1-0984, N00014-10-1-0355, N00014-14-1-0390), FR Ministry of Defence (DGA; public market no. 15860052), World Wildlife Fund Norway (9E0682), and French Total Foundation and Bleustein-Blanchet Foundation. The statistical development work was supported by a separate grant from the U.S. Office of Naval Research (N00014-12-1-0204), under the project entitled Multi-study OCean acoustics Human effects Analysis (MOCHA). Time allocation to different activities and habitats enables individuals to modulate their perceived risks and access to resources, and can reveal important trade-offs between fitness-enhancing activities (e.g., feeding vs. social behavior). Species with long reproductive cycles and high parental investment, such as marine mammals, rely on such behavioral plasticity to cope with rapid environmental change, including anthropogenic stressors. We quantified activity budgets of free-ranging long-finned pilot whales in order to assess individual time trade-offs between foraging and other behaviors in different individual and ecological contexts, and during experimental sound exposures. The experiments included 1-2 and 6-7 kHz naval sonar exposures (a potential anthropogenic stressor), playback of killer whale (a potential predator/competitor) vocalizations, and negative controls. We combined multiple time series data from digital acoustic recording tags (DTAG) as well as group-level social behavior data from visual observations of tagged whales at the surface. The data were classified into near-surface behaviors and dive types (using a hidden Markov model for dive transitions) and aggregated into time budgets. On average, individuals (N=19) spent most of their time (69%) resting and transiting near surface, 21% in shallow dives (depth

Exposure to underwater sound can cause permanent hearing loss and other physiological effects in marine animals. To reduce this risk, naval sonars are sometimes gradually increased in intensity at the start of transmission (‘ramp-up’). Here, we conducted experiments in which tagged humpback whales were approached with a ship to test whether a sonar operation preceded by ramp-up reduced three risk indicators – maximum sound pressure level (SPLmax), cumulative sound exposure level (SELcum) and minimum source–whale range (Rmin) – compared with a sonar operation not preceded by ramp-up. Whales were subject to one no-sonar control session and either two successive ramp-up sessions (RampUp1, RampUp2) or a ramp-up session (RampUp1) and a full-power session (FullPower). Full-power sessions were conducted only twice; for other whales we used acoustic modelling that assumed transmission of the full-power sequence during their no-sonar control. Averaged over all whales, risk indicators in RampUp1 (n=11) differed significantly from those in FullPower (n=12) by −3.0 dB (SPLmax), −2.0 dB (SELcum) and +168 m (Rmin), but not significantly from those in RampUp2 (n=9). Only five whales in RampUp1, four whales in RampUp2 and none in FullPower or control sessions avoided the sound source. For RampUp1, we found statistically significant differences in risk indicators between whales that avoided the sonar and whales that did not: −4.7 dB (SPLmax), −3.4 dB (SELcum) and +291 m (Rmin). In contrast, for RampUp2, these differences were smaller and not significant. This study suggests that sonar ramp-up has a positive but limited mitigative effect for humpback whales overall, but that ramp-up can reduce the risk of harm more effectively in situations when animals are more responsive and likely to avoid the sonar, e.g. owing to novelty of the stimulus, when they are in the path of an approaching sonar ship., his work was supported by the Office of Naval Research [N00014-10-1-0355], The Netherlands Ministry of Defence, Norwegian Ministry of Defence and French Ministry of Defence. Additional support was provided through a PhD studentship withmatched funding from The Netherlands Ministry of Defence and the Natural Environment Research Council [NE/J500276/1 to P.J.W.]; and the MASTS (The Marine Alliance for Science and Technology for Scotland) pooling initiative to P.L.T. MASTS is funded by the Scottish Funding Council [HR09011] and contributing institutions.

The revision of the French method for road traffic noise prediction (NMPB-Routes-2008) is now published. The major principles of NMPB-Routes-2008 are outlined. The most important modifications regarding the source are the reduction of its height and the introduction of two different spectra. In this complete revision, the main change is the replacement of the ISO 9613-2-based ground attenuation formula in downward-refraction conditions by the formula for ground attenuation in homogeneous conditions of NMPB-Routes-1996 with corrected heights in order to take into account the mean curvature of rays (refraction) and its scattering (turbulence). NMPB-Routes-2008 adds an attenuation term for an occasional cutting embankment. Regarding diffraction the dif formula is now more suitable for low height barriers. The validation of NMPB-Routes-2008 with respect to experiment is presented. It is based on measurement campaigns on 6 sites with complex geometries and shows that the predicted noise levels obtained from NMPB-Routes-2008 are significantly closer to experimental results than in the case of the original method. S. Hirzel Verlag.

We would like to thank 3S partners and funders especially for enabling this research (NL Ministry of Defence, NOR Ministry of Defence, US Office of Naval Research, and World Wildlife Fund, Norway). PLT was supported by the Scottish Funding Council (grant HR09011) through the Marine Alliance for Science and Technology for Scotland. The time and energetic costs of behavioral responses to incidental and experimental sonar exposures, as well as control stimuli, were quantified using hidden state analysis of time series of acoustic and movement data recorded by tags (DTAG) attached to 12 sperm whales (Physeter macrocephalus) using suction cups. Behavioral state transition modeling showed that tagged whales switched to a non-foraging, non-resting state during both experimental transmissions of low-frequency active sonar from an approaching vessel (LFAS; 1-2 kH z, source level 214 dB re 1 μPa m, four tag records) and playbacks of potential predator (killer whale, Orcinus orca) sounds broadcast at naturally occurring sound levels as a positive control from a drifting boat (five tag records). Time spent in foraging states and the probability of prey capture attempts were reduced during these two types of exposures with little change in overall locomotion activity, suggesting an effect on energy intake with no immediate compensation. Whales switched to the active non-foraging state over received sound pressure levels of 131-165 dB re 1 μPa during LFAS exposure. In contrast, no changes in foraging behavior were detected in response to experimental negative controls (no-sonar ship approach or noise control playback) or to experimental medium-frequency active sonar exposures (MFAS; 6-7 kH z, source level 199 re 1 μPa m, received sound pressure level [SPL] = 73-158 dB re 1 μPa). Similarly, there was no reduction in foraging effort for three whales exposed to incidental, unidentified 4.7-5.1 kH z sonar signals received at lower levels (SPL = 89-133 dB re 1 μPa). These results demonstrate that similar to predation risk, exposure to sonar can affect functional behaviors, and indicate that increased perception of risk with higher source level or lower frequency may modulate how sperm whales respond to anthropogenic sound. Publisher PDF

Modern long-range naval sonars are a potential disturbance for marine mammals and can cause disruption of feeding in cetaceans. We examined the lunge-feeding behaviour of humpback whales Megaptera novaeangliae before, during and after controlled exposure experiments with naval sonar by use of acoustic and motion sensor archival tags attached to each animal. Lunge-feeding by humpback whales entails a strong acceleration to increase speed before engulfing a large volume of prey-laden water, which can be identified by an acoustic signature characterized by a few seconds of high-level flow-noise followed by a rapid reduction, coinciding with a peak in animal acceleration. Over 2 successive seasons, 13 humpback whales were tagged. All were subject to a no-sonar control exposure, and 12 whales were exposed to 2 consecutive sonar exposure sessions, with 1 h between sessions. The first sonar session resulted in an average 68% reduction in lunge rate during exposure compared to pre-exposure, and this reduction was significantly greater than any changes observed during the no-sonar control. During the second sonar session, reduction in lunge rate was 66% during sonar exposure compared to the pre-exposure level, but was not significant compared to the no-sonar control, likely due to a larger inter-individual variability because some individuals appeared to have habituated whereas others had not. Our results indicate that naval sonars operating near humpback whale feeding grounds may lead to reduced foraging and negative impacts on energy balance. © 2016 The authors.

The study was funded by the US Office of Naval Research, The Netherlands Ministry of Defence, Norwegian Ministry of Defence and French Ministry of Defence. F.V., C.C., P.K., F.P.L. and P.M. were supported by one or two of these funders. P.T. received funding from the MASTS pooling initiative (The Marine Alliance for Science and Technology for Scotland). MASTS is funded by the Scottish Funding Council (grant reference HR09011) and contributing institutions. Social interactions among animals can influence their response to disturbance. We investigated responses of long-finned pilot whales to killer whale sound playbacks and two anthropogenic sources of disturbance: Tagging effort and naval sonar exposure. The acoustic scene and diving behaviour of tagged individuals were recorded along with the social behaviour of their groups. All three disturbance types resulted in larger group sizes, increasing social cohesion during disturbance. However, the nature and magnitude of other responses differed between disturbance types. Tagging effort resulted in a clear increase in synchrony and a tendency to reduce surface logging and to become silent (21% of cases), whereas pilot whales increased surface resting during sonar exposure. Killer whale sounds elicited increased calling rates and the aggregation of multiple groups, which approached the sound source together. This behaviour appears to represent a mobbing response, a likely adaptive social defence against predators or competitors. All observed response-Tactics would reduce risk of loss of group coordination, suggesting that, in social pilot whales, this could drive behavioural responses to disturbance. However, the behavioural means used to achieve social coordination depends upon other considerations, which are disturbance-specific. Publisher PDF

Anti-predator strategies are often defined as ‘flight’ or ‘fight’, based upon prey anatomical adaptations for size, morphology and weapons, as well as observed behaviours in the presence of predators. The humpback whale Megaptera nova eangliae is considered a ‘fight’ specialist based upon anatomy and observations of grouping behaviour and active defence when attacked by killer whales. However, the early stage of humpback whale anti-predator strategy, when the prey detects the presence of a distant potential predator that may not have perceived it, has never been described. Our aim was to experimentally examine this initial stage of anti-predator responses. Humpbacks are likely to hear well at the frequencies of killer whale vocalisations, thus the perception of killer whale sounds could trigger anti-predator responses. To address this hypothesis, we played mammal-eating killer whale sounds to 8 solitary or paired humpback whales in North Atlantic feeding grounds and monitored their behavioural responses. We found that predator sound playbacks induced a cessation of feeding, a change in the diving pattern and a clear directional and rapid horizontal avoidance away from the speaker. Interestingly, in mothercalf pairs with young calves, the directional horizontal avoidance was atypically alternated by 90 degree turns, which may serve as a mechanism to better track the pre dator or a stealth tactic when more vulnerable animals are present. These results provide experimental evidence that humpback whales can exhibit a strong horizontal avoidance as an initial stage of anti-predator defence, indicating that anti-predator responses may be more graded and mixed than previously recognized. Publisher PDF Publisher PDF

Contributions of P.M., P.T., C.C., S.D., F.V., P.W., L.M.L., T.N. and S.H. were funded by the US Office of Naval Research. Contributions of P.K., L.K. and L.S. were funded by the Norwegian Ministry of Defence. Contributions of F.L., S.v.IJ. and A.v.B. were funded by The Netherlands Ministry of Defence. Fieldwork contributions of L.M.L. and T.N. were funded by the Strategic Environmental Research and Development Program (SERDP). The analysis component of L.M.L.'s contribution was funded by DGA French Ministry of Defence. P.T. acknowledges the support of the MASTS pooling initiative (The Marine Alliance for Science and Technology for Scotland) in the completion of this study. MASTS is funded by the Scottish Funding Council (grant no. HR09011) and contributing institutions. Although northern bottlenose whales were the most heavily hunted beaked whale, we have little information about this species in its remote habitat of the North Atlantic Ocean. Underwater anthropogenic noise and disruption of their natural habitat may be major threats, given the sensitivity of other beaked whales to such noise disturbance. We attached dataloggers to 13 northern bottlenose whales and compared their natural sounds and movements to those of one individual exposed to escalating levels of 1–2 kHz upsweep naval sonar signals. At a received sound pressure level (SPL) of 98 dB re 1 μPa, the whale turned to approach the sound source, but at a received SPL of 107 dB re 1 μPa, the whale began moving in an unusually straight course and then made a near 180° turn away from the source, and performed the longest and deepest dive (94 min, 2339 m) recorded for this species. Animal movement parameters differed significantly from baseline for more than 7 h until the tag fell off 33–36 km away. No clicks were emitted during the response period, indicating cessation of normal echolocation-based foraging. A sharp decline in both acoustic and visual detections of conspecifics after exposure suggests other whales in the area responded similarly. Though more data are needed, our results indicate high sensitivity of this species to acoustic disturbance, with consequent risk from marine industrialization and naval activity. Publisher PDF

Controlled exposure experiments using 1 to2 kHz sonar signals were conducted with 11 humpback whales (Megaptera novaeangliae), one minke whale (Balaenoptera acutorostrata), and one northern bottlenose whale (Hyperoodon ampullatus) during three field trials from 2011 to 2013. Ship approaches without sonar transmis-sions, playbacks of killer whale vocalizations, and broadband noise were conducted as controls. Behavioural parameters such as horizontal movement, diving, social interactions, and vocalizations were recorded by animal-attached tags and by visual and acoustic tracking. Based on these data, two expert panels independently scored the severity of behavioural changes that were judged likely to be responses to the experimental stimuli, using a severity scale ranging from no effect (0) to high potential to affect vital rates (9) if exposed repeatedly. After scoring, consensus was reached with a third-party moderator. In humpback whales, killer whale playbacks induced more severe responses than sonar exposure, and both sonar exposures and killer whale playbacks induced more responses and responses of higher severity than the no-sonar ship approaches and broadband noise playbacks. The most common response during sonar exposures in all three species was avoidance of the sound source. The most severe responses to sonar (severity 8) were progressive high-speed avoidance by the minke whale and long-term area avoidance by the bottlenose whale. Other severe responses included prolonged avoidance and cessation of feeding (severity 7). The minke whale and bottlenose whale started avoiding the source at a received sound pressure level (SPL) of 146 and 130 dB re 1 μPa, respectively. Humpback whales generally had less severe responses that were triggered at higher received levels. The probability of severity scores with the potential to affect vital rates increased with increasing sound exposure level (SEL). The single experiments with minke and bottlenose whales suggest they have greater susceptibility to sonar disturbance than humpback whales, but additional studies are needed to confirm this result.

During outdoor measurements, specific windscreens are often used to prevent rain water to penetrate into the microphone and to damage its components, but some water can nevertheless remain in the foam of the windscreen. This paper presents an extensive experimental study of the influence of water in the foam of a windscreen on its frequency response. It is concluded that the presence of water inside a windscreen can significantly change the sensitivity of the system only for rain amount higher than 1 mm and for frequency above 1 kHz. Some disparities can be found between the different types of windscreens. Bias correction values, together with uncertainty estimations are given for different types of windscreens and an estimation of the duration during which correction and uncertainty must be applied is also proposed for several types of common windscreens.

In Europe, in situ measurements of sound reflection and airborne sound insulation of noise barriers are usually done according to CEN/TS 1793-5. This method has been improved substantially during the EU funded QUIESST collaborative project. Within the same framework, an inter-laboratory test has been carried out to assess the repeatability and reproducibility of the newly developed method when applied to real-life samples, including the effect of outdoor weather variability and sample ageing. This article presents the statistical analysis of the inter-laboratory test results, and the values of the repeatability and the reproducibility, both for one-third octave bands and for the single-number ratings. The estimated reproducibility values can be used as the extended measure of uncertainty at the 95% credibility level in compliance with the ISO GUM. The repeatability and reproducibility values associated with airborne sound insulation are also compared with the corresponding values for laboratory measurements in building acoustics and an acceptable agreement is found.

Equivalent acoustic source height is an important parameter for accurate predictions of the acoustic impact of transportation infrastructures. Research has shown that this parameter can be obtained from a two-microphone technique in the case of one broadband omnidirectional point source above an homogeneous ground, modeled as a Delany-Bazley absorber. It is shown in this paper that this method can be generalized to n broadband sources with same height, above an homogeneous ground or a ground with an impedance discontinuity. All sources are considered to have the same emission spectrum. The method is based on the comparison of the level difference spectrum between two microphones - hereinafter called attenuation spectrum - measured and computed. Numerical and experimental validations confirm the reliability of the method for controlled noise sources. Furthermore, it is demonstrated that qualitative assessment of ground parameters is sufficient to obtain an accurate source height determination.